心脏康复运动中应用心率血压乘积对心肌缺血监控的研究

Application of Rate Pressure Product in Ischemia Monitoring during Exercise Based Cardiac Rehabilitation

目的:探讨冠心病患者康复运动中心肌供血和心血管功能的变化,应用心率血压乘积为他们运动中心肌缺血的监控提供简便的措施。方法:54名男性冠心病患者(均处于稳定期)在活动跑台上进行症状限制性运动试验,在运动试验的第I级负荷末、第II级负荷末和第III级负荷末对受试者的心率、收缩压和舒张压进行测试,并依此计算心率血压乘积((心率×收缩压)/100),其间连续观察他们12导联心电图中ST段水平的变化。结果:(1)运动试验中,ST段水平下降较少的患者其心血管反应也较小,而ST段水平下降较多的患者不但在第I级负荷时就出现了较大的心血管反应,而且在其后的运动中他们心血管反应又有较大幅度的上升;(2)在改良布鲁斯跑台方案第Ⅲ级负荷时,ST段水平下降达到1 mm(心内膜下急性局部缺血的临界值)的患者其心率血压乘积数值超过了200。结论:心率血压乘积能较好地反映受试者的心血管状态和整体健康水平。冠心病患者在康复运动中,如果心率血压乘积表现出突然的增加,这可能是潜在的心肌供血不足的反映。

Objective：To investigate changes of myocardial blood supply and cardiovascular function when coronary heart disease patients undertake exercise,and to provide a simple manner for them to monitor cardiac ischemia by applying rate pressure product. Method：Fifty-four male recent coronary heart disease patients performed a graded exercise test on a treadmill. Both heart rate and systolic/diastolic blood pressure were measured at the last minute of I ,II and III exercise stage. Rate-pressure product was then calculated by multiplying heart rate by systolic blood pressure and divided the product by 100. A 12 lead electrocardiogram was monitored continuously and from which changes of ST segment level could be found. Results：1）The patients with less ST segment depression during exercise showed a light cardiovascular response at the moment. Whereas those with more ST segment depression not only depicted a significant cardiovascular response at exercise stage I but also presented much increase for this response thereafter. 2）The patients with ST segment depression reaching 1 mm at exercise stage III of the modified Bruce treadmill protocol demonstrated a relative large rate pressure product value ,over 200 for instance. Conclusions：Cardiovascular status and state of health of the subjects can be reflected by rate pressure product response. We should be aware that if rate pressure product shows a sudden increase when coronary heart disease patients undertaking exercise during rehabilitation ,it might be related to underlying myocardial insufficiency.